As close as I was able to get to one of those huge wind turbines, I did not see any evidence of dead birds. The time was summer, in farm country. More important, none of us could hear any sound from the thing at all. So I qestion a bit the claims made in both of the areas.

 

I don't know about noise but I've seen a hawk strike a blade and go down. Perhaps it happens once in a while, or maybe it happens more often. Whomever is making the claim just MIGHT be exaggerating it just to take a stance against wind power. Who knows the real reason why. But I know what I've seen. One bird strike.

If I were ever to set up a wind turbine it would be one of those types that look like an S shape and no matter what direction the wind blows - it turns. They say they turn with relatively light breezes as well. I don't know that. But it's probably less likely to injure aviary life in the process. Incidentally, the strike I saw was of a hawk hunting. Likely its gaze was focused at the ground and the blade that struck it came from above. But that's merely conjecture on my part.

I'd collect solar and wind as well as rain water, and even experiment with collecting water from humid air. Use green resources as much as possible - IF money were not a limiting factor. Insulate to keep a house warm in the winter and cool in the summer. I recall back in Connecticut, a forest. During hot days I'd stroll into the forest where it was definitely cool. Not cold but definitely cool. A sweatshirt would not be uncomfortably warm. So if I could live near a stand of trees and undergrowth like that - I'd consider running ductwork to gather that cool air and bring it in to the house for cooling without using any more energy than a fan. (but that's all just a dream; an imagination - gone wild maybe)

 

Tony, Of course a healthy forest will be cooler on a warm summer day. Water evaporating from the leaves absorbs a fair amount of energy, thus assuring that it will be cooler. That is how plants work: capillary action driven by evaporation. Simple in concept and very reliable, and a complement to rainfall that returns the water to the ground. The area to avoid a home among the trees would be California, since that area has both live and dead trees and not enough water. Wildfire is very destructive and with many years of dead stuff accumulating there is lots of very dry fuel for huge fires spreading rapidly. Not an area that I would even choose to visit.
If you have enough property and adequate determination, instead of cool forest air you can bury glazed tile drain pipes perhaps six feet down and blow air through them for cooling. The moist, or even wet, ground can absorb a whole lot of heat, and cool the air in the process. If the tunnel is big enough it can serve as the storage space for the supplies for your fallout shelter/tornado shelter.
Solar power is a good idea where there are adequate sunshine hours most days, not the case where I live, but lots of other areas work well. At some point I may be able to put a small wind turbine up on my radio tower, although my wife says no. So it would be done while she is not looking.

 

 

Interesting read! I am afraid I may have skimmed to quickly. I have a couple of friends who have had solar "consultants" come to their house, occupy 2.5 hours of their evening and then give them their recommendation. You would think that in 2.5 hours they could have educated the people...but all they managed to do was show pictures of their own equipment and make vague empty statements about effectiveness. I saw one of these guys - I swear I saw him sitting on an elephant on a tv commercial late at night trying to sell used Yugos The most criminal aspect of it is all, imho, was that their options for back-up generators were cheap (flimsy) and not adequate. I have bought some property that is going to require me to generate my own electricity but I did a lot of homework beforehand. From personal observation, one of the reasons why solar can be so expensive is that so many people now have cavernous homes - huge - that require lots of juice to keep their a/c running or to keep the lights going in it. Because of this, I am looking at house designs no more than 1,000 sq ft...with lots of insulation....windows placed not for decorative purposes but for the sake of making natural lighting useful...I hope I have better luck than the average person

 

Further, for all intents and purposes, the "sky" is a closed surface (2D), not a volume (3D).

Azimuth and declination is all any astronomer has ever needed. If 2D is enough for astronomy, it’s enough for a solar panel.

Hi,

To both of you, i already acknowledged that you can 'call' it 2d, but that 'surface' you speak of exists in 3d space. It doesnt matter that we dont 'need' one of the dimensions.
Also, what is it that we dont 'need' and why do we have to state that we dont 'need' it? It's another dimension.
Also, the only way to generate that 'surface' is in 3d space.

I have a box sitting right here sort of next to me. I dont care how tall it is, but the base is 8 by 12 inches. Does that make it a 2d box?

Another question:
If i use a single light sensor, why do i have to take more than one reading to know which way to tilt the panel? It's because curves are already 2d.

 

@pengyou: Don't forget light pipes, those pipes that bring sunlight from the roof into the room via a highly reflective pipe into a defuser inside the home.

I have a swamp cooler (evaporative cooler) that works very well in this region. For a while I considered installing air conditioning, rendering the swamp cooler useless. But there's a 14 inch duct that could easily house a light pipe to bring sunlight directly into the main hallway. It's location would also light up the kitchen and the living room.

There are tons of things you can do. Depending on your location, some things will prove more beneficial than other locations. But I find it funny when I see things on the TV that advertise their product: "Take this little orange pill and it can help you lose weight up to 75% faster." Two key factors that make their statement true: "CAN HELP". People hear that and conclude that it DOES help. And there's no proof that it "CAN'T help" either. The other statement that's laughable is "up to 75% faster." Faster than WHAT? - - - An old cell phone commercial made the claim that "Nobody has a more powerful network." Which is absolutely true. The key is "More powerful". They're all regulated by the FCC (United States), so everybody is using the maximum possible power. The ad didn't say theirs was the MOST powerful, only that nobody had a MORE powerful network, leaving the consumer to believe theirs had the MOST powerful network available. You've got to listen carefully. These things have been crafted to meet truth in advertising, meaning they're not allowed to LIE to you, so they use speech that allows you to ASSUME their product is better than all others.

I've had solar salesmen here too. They gave me the impression my bills would be (summer time) around 9¢ a month, and in the winter time bills around $3.00 (US currency). Claims like that are fraudulent. And you had to pick out the truth from their insinuations. Then, it so happened, I was selling a pet. The woman who purchased him worked in the solar industry. She asked what our bills were like and told us flat out that solar would be a huge waste of our time. By the time it was paid off I'd be needing a new system. No gain there. So you really need to listen carefully to EVERY word they tell you because they'll tell you nothing and make it sound like everything. I have not yet gone solar.

Some years back I heard someone was developing a new sort of solar panel, one that had a much higher efficiency. So far I've not heard anything new about that. Something about using infrared AND visible light spectrums. If memory serves, the new panels have something like three spectrums they are designed to work in. I could be wrong. But solar will probably not be viable where I am until I'm 90. And that depends on how the climate patterns may change. Utah could become the next Washington State (cloudy most of the time).

 

Interesting read! I am afraid I may have skimmed to quickly. I have a couple of friends who have had solar "consultants" come to their house, occupy 2.5 hours of their evening and then give them their recommendation. You would think that in 2.5 hours they could have educated the people...but all they managed to do was show pictures of their own equipment and make vague empty statements about effectiveness. I saw one of these guys - I swear I saw him sitting on an elephant on a tv commercial late at night trying to sell used Yugos The most criminal aspect of it is all, imho, was that their options for back-up generators were cheap (flimsy) and not adequate. I have bought some property that is going to require me to generate my own electricity but I did a lot of homework beforehand. From personal observation, one of the reasons why solar can be so expensive is that so many people now have cavernous homes - huge - that require lots of juice to keep their a/c running or to keep the lights going in it. Because of this, I am looking at house designs no more than 1,000 sq ft...with lots of insulation....windows placed not for decorative purposes but for the sake of making natural lighting useful...I hope I have better luck than the average person

Hi,

Sounds interesting. Back in the 80's i got to see a huge house that was made to use solar electric and solar heating. Huge tanks filled with rocks for storing hot water. Large solar panel with one of our solar converters (that's why i went in the first place). I think it was in Connecticut. The house was part experimental, and would sell today for around 10 million. Everything was computer controlled too. Very interesting to see that.

 

(response to post # 167) One of the most beneficial courses that I had in high school was in ninth grade when the social studies teacher spent a bunch of time teaching us about propaganda. Being able to recognize it in advertising and in the news and in general commentary is still valuable now that I am retired. I wonder if such a course is offered anywhere presently, because it would be of even more value today, given that half of everything we hear is lies. At least that is what it seems like. some may just be mild exaggeration while other is just totally devoid of any truth.
And like in the picture, solar power may not be as effective when the cells are covered with snow. Or when the days are very cloudy, or when the rain is pouring down. But in much of Arizona things are different.
I do wonder about here because I see assorted traffic signs with solar arrays to charge their battery packs, and I see some houses and businesses with solar arrays. AND, along interstate 94, between Detroit and Chicago, there is a casino with a huge solar array. Of course, it may only be for show, since everything about a casino is intended to be a departure from reality. Does anybody have any actual information about that place??

 

Or during a snowy Oregon winter.

 

Hi,

I was talking with a friend a week or two ago about defrosting the panels once they had ice or snow on top. It is possible to make the panels slightly warm by pumping a current through the panel. They are just like diodes connected in series and parallel and would get warm and warm is sometimes enough to melt ice. We did not yet calculate the energy requirement to do this however, and wondered if it would take a whole day's worth of energy collecting just to defrost one time.

These secondary problems seem to find their way into even the best application ideas.

 

We did not yet calculate the energy requirement to do this however, and wondered if it would take a whole day's worth of energy collecting just to defrost one time.

You'd need 80 calories (4.12J * 80) for each gram of ice -- assuming the ice is already at 0°C.

Fortunately, you need not melt the entire bulk of ice -- just the ice at the interface where it contacts the glass. If the inclination is steep enough, the remaining ice will just slide down the face, lubricated by the melted ice.

Unfortunately, if the ambient temp is below (well below?) 0°C, then any heat you add may just radiate/convect/conduct to the environment before enough heat has accumulated to melt your first gram of ice. Therefore, any de-icing energy is simply wasted.

Sometimes, the only way to win is to not play the game.

 

You'd need 80 calories (4.12J * 80) for each gram of ice -- assuming the ice is already at 0°C.

Fortunately, you need not melt the entire bulk of ice -- just the ice at the interface where it contacts the glass. If the inclination is steep enough, the remaining ice will just slide down the face, lubricated by the melted ice.

Unfortunately, if the ambient temp is below (well below?) 0°C, then any heat you add may just radiate/convect/conduct to the environment before enough heat has accumulated to melt your first gram of ice. Therefore, any de-icing energy is simply wasted.

Sometimes, the only way to win is to not play the game.

I just use a push broom or a solar panel rake to clear snow.

 

I used to have satellite TV (a dish on the roof). Snow would accumulate on the nearly vertical surface and block the signal. So I put a low voltage heating patch on the back side of it. When snow became a problem I'd manually turn the heater on (on a timer) and run it for a half hour. Usually within 5 minutes the snow had warmed enough to slip off the face of the dish. Only ran it for a half hour because the timer I had was settable in half hour increments.

Here (northern Utah) winter temperatures average a low of mid 20's (in Fahrenheit). Daytime highs average in the mid 30's, so to JoeyD's point, radiative cooling has never been a factor. With snow comes cloud cover, which holds in heat. Those rare teens, very rare single digits and those news worthy below zero degrees often don't have snow accompanying them.

Melting accumulated snow hasn't been much of an issue in Utah, as our average daytime highs often melt what has fallen. It tends to stick on the grass but rarely sticks around on the driveway. Especially if you've shoveled, snow-blown or plowed the surface. And winters have been growing more and more mild. The days of a 10 inch valley snowfall have become exceedingly rare. Every year we fear the next winter because the last one was so mild. Never seems to come. So snow on a solar panel would be rectified by nature of the climate.

 

A satellite dish is one thin layer of metal, while most solar cells have a layer of metal to support the cover and the solar cell material. So heating a solar cell from the back would be much different. AND on the cloudy days when there is no direct sunshine the solar heat input will be much less. Even heating the cells by running current through them will not be adequate. In addition, we get icy snow that sticks to everything here in Michigan. So some areas are not suitable for solar arrays to serve as primary power sources.

 

I just use a push broom or a solar panel rake to clear snow.

How much energy does that take?

 

Using a push broom on roof mounted solar cells would take a fair amount of effort climbing up to the roof, and present a very real challenge in staying on that sloping snow covered roof while sweeping the snow off. And sliding off and falling 20 feet would be quite painful at best. I try to avoid damage and pain at those magnitudes.
In addition, there is always the chance of damaging the solar cells when using a push broom to clean them.

 

Using a push broom on roof mounted solar cells would take a fair amount of effort climbing up to the roof, and present a very real challenge in staying on that sloping snow covered roof while sweeping the snow off. And sliding off and falling 20 feet would be quite painful at best. I try to avoid damage and pain at those magnitudes.
In addition, there is always the chance of damaging the solar cells when using a push broom to clean them.

Spoken by a person who doesn't seem to know about snow rakes.

Push brooms are for ground mounts and rakes are for roofs. The panels have taken some good hail hits without a problem, don't think a soft bristle broom will hurt.

 

How much energy does that take?

It's part of the winter exercise routine.

 

I am so glad we never get snow! My wife grew up in it and is happy to never see it again.
Our solar panels are working really well and it is so nice to get a bill that the power Co. pays us
I'm convinced the trick is to get lots of panels. A small system is almost not worth it I think. Our 10KW has saved us a lot of money in the power we have used, and now the feed in tariff is working, we get that as an added bonus. But I installed it not for the feed in tariff but to offset our large power usage.
Location makes a big difference in the viability.